tsl transpiler not supporting "switch"

[Makio64]

Description

currently the transpiler seems not understanding the switch :

vec2 get_vertex(int id)
{
    switch(id){
        case 0: return vec2(1.);
        case 1: return vec2(2.);
        case 2: return vec2(3.);
        case 3: return vec2(4.);
        default: return vec2(0.);
    }
}

transpile to :

import { int, Fn } from 'three/tsl';

export const get_vertex = /*#__PURE__*/ Fn( ( [ id_immutable ] ) => {

	const id = int( id_immutable ).toVar();
	switch( id );

} ).setLayout( {
	name: 'get_vertex',
	type: 'vec2',
	inputs: [
		{ name: 'id', type: 'int' }
	]
} );

Edit : actually i'm not even sure switch is supported by tsl cause it's not in the doc :
https://github.com/mrdoob/three.js/wiki/Three.js-Shading-Language

Live example

https://threejs.org/examples/webgpu_tsl_transpiler.html

Version

r175

[Mugen87]

Edit : actually i'm not even sure switch is supported by tsl cause it's not in the doc 👍

You are right, there is no Switch()/Case() syntax yet.

You can represent a switch statement always as an if/else statement so we could basically updated the transpiler to do that.

However, given that GLSL and WGSL support switch statements, adding a switch/case syntax could be a worthwhile addition. Maybe like so?

import { Switch, vec2 } from 'three/tsl';

const result = vec2();

Switch( id ).Case( 0, () => {

	result.assign( 1 );

} ).Case( 1, () => {

	result.assign( 2 );

} ).Case( 2, () => {

	result.assign( 3 );

} ).Case( 3, () => {

	result.assign( 4 );

} ).Default( () => {

	result.assign( 0 );

} );

[Makio64]

@Mugen87 I'm closing this issue, thanks for the fast support on it !

[Mugen87]

The transpiler does not support the new switch/case syntax though. It might be good for tracking to keep this issue open.

[Makio64]

@Mugen87 oh right my bad ! thanks !